what RAID should I use?

I am trying to set up a rack mount database server and wanted to find out what sort of fault tolerance to use? I expect a max of perhaps 200GBs in the future. It seems I could mirror the OS using two drives and then leave the rest as a RAID 5 configuration. This is a MS SQL 2000 server with datafiles stored locally. Would there be a significant difference with using Windows 2000 software RAID 5 as opposed to hardware RAID?
Performance issues?